Shulchan Arukh, Orach Chayim 271:13ืฉืืืื ืขืจืื, ืืืจื ืืืื ืขืจืดื:ืืดื
13. One must drink a cheekful from the Kiddush cup, i.e. if one moves all the wine to one side of their mouth and their cheek appears full, and this is the majority of a Revi'it.
ืฆืจืื ืืฉืชืืช ืืืืก ืฉื ืงืืืืฉ ืืืื ืืืืืื ืืืืื ื ืื ืฉืืกืืงื ื ืืฆื ืืื ืืคืื ืืืจืื ืืื ืืืืืื ืืืื ืจืืื ืฉื ืจืืืขืืช:
Eruvin 79b:13ืขืืจืืืื ืขืดื ื:ืืดื
Rava said: The elders of Pumbedita, Rav Yehuda and his students, stated these two matters. One was this mentioned above with regard to lifting the barrel; and the other was: With regard to one who recites kiddush over wine on Shabbat or a Festival, if he tasted a mouthful of wine, he fulfilled his obligation; however, if he did not taste a mouthful, he did not fulfill his obligation.
ืึธืึทืจ ืจึธืึธื: ืึธื ึตื ืชึผึทืจึฐืชึผึตื ืึดืืึผึตื, ืกึธืึตื ืึฐืคืึผืึฐืึผึฐืึดืืชึธื ืึทืึฐืจึดืื ึฐืืึผ: ืึฒืึธื โ ืึธื. ืึดืืึผึทืึฐ โ ืึทืึฐืงึทืึผึตืฉื, ืึดื ืึธืขึทื ืึฐืึนื ืืึผืึฐืึธืื โ ืึธืฆึธื, ืึฐืึดื ืึธืื โ ืึนื ืึธืฆึธื.
Pesachim 107a:11ืคืกืืื ืงืดื ื:ืืดื
With regard to the halakha that one who recites kiddush must drink from the cup, the Gemara states that one fulfills the mitzva of kiddush by tasting any amount of wine. Rabbi Yosei, son of Yehuda, says that one must drink at least a cheekful. Rav Huna said that Rav said, and Rav Giddel from the city of Neresh likewise teaches: One who recites kiddush and tastes a cheekful has fulfilled his obligation, and if not, he has not fulfilled his obligation.
ืึทืึฐืขึถืืึถืช ืึทืึดื ืึผืื ืฉืึถืืึผื. ืจึทืึผึดื ืืึนืกึตื ืึผึทืจ ืึฐืืึผืึธื ืืึนืึตืจ: ืึฐืึนื ืืึผืึฐืึธื. ืึธืึทืจ ืจึทื ืืึผื ึธื ืึธืึทืจ ืจึทื, ืึฐืึตื ืชึผึธื ึตื ืจึทื ืึผึดืืึผึตื ืึผึฐืึดื ื ึธืจึถืฉื: ืึทืึฐืงึทืึผึตืฉื ืึฐืึธืขึทื ืึฐืึนื ืืึผืึฐืึธื โ ืึธืฆึธื, ืึฐืึดื ืึธืื โ ืึนื ืึธืฆึธื.
Mishnah Berurah 271:65ืืฉื ื ืืจืืจื ืขืจืดื:ืกืดื
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(ืกื) ืืืื ืืืืืื - ืืืขืื ื ืฉืืขืืจ ืืฉืื ืฉืชืชืืฉื ืืขืชื ืขื"ื:
Tosafot on Eruvin 79b:13:1ืชืืกืคืืช ืขื ืขืืจืืืื ืขืดื ื:ืืดื:ืืณ
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ืื ืืขื ืืื ืืืืืื - ืคืืจืฉ ืจ"ืช ืืื ืืื ืืืืืื ืืื ืืืืงื ืืื ืืืืืื ืืื ืจ"ื ืืืืคืจืฉ ืืค' ืืชืจื ืืืืื (ืืฃ ืค.) ืื ืฉืืืื ืืกืืงื ืืฆื ืืื ืื ืจืื ืืืื ืืืืื ืืืค' ืืชืจื ืืืืื (ืฉื) ืืืื ืืืื ืืืืืื ื ืคืืฉ ืืจืืืขืืช ืืืขืจืื ืคืกืืื (ืืฃ ืงื:) ืืืจ ืืืืจืืข ืืืกืืช ืืฉ ืฉืืขืืจ ืจืืืขืืช ืืืืก ืฉื ืงืืืืฉ ืืื ืืื ืืืื ืืืขืื ืืื ืืืืื ืื ืืื ืื ืื ืื:
Rashbam on Pesachim 107a:11:2ืจืฉื"ื ืขื ืคืกืืื ืงืดื ื:ืืดื:ืืณ
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ืืืขื ืืื ืืืืื ืืฆื ืืื ืืื ืื ืืฆื - ืืืื ืืืืืชื ืืืื ืฉืื ืืขื ืืื ืืื ืืืกืืืื ืืื ืืขื ืืื ืืื ืืฆืื ืืืื ืืื ืืืืชื ืืืข"ืค ืฉืื ืืขืื: